US4944488A - Gate valve - Google Patents

Gate valve Download PDF

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Publication number
US4944488A
US4944488A US07/436,120 US43612089A US4944488A US 4944488 A US4944488 A US 4944488A US 43612089 A US43612089 A US 43612089A US 4944488 A US4944488 A US 4944488A
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US
United States
Prior art keywords
valve
gate
chamber
stem
valve chamber
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US07/436,120
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English (en)
Inventor
Peter D. Clayson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alberta Ltd
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Alberta Ltd
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Publication date
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Publication of US4944488A publication Critical patent/US4944488A/en
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Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K27/00—Construction of housing; Use of materials therefor
    • F16K27/04—Construction of housing; Use of materials therefor of sliding valves
    • F16K27/044—Construction of housing; Use of materials therefor of sliding valves slide valves with flat obturating members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
    • F16K3/02—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor
    • F16K3/12—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor with wedge-shaped arrangements of sealing faces

Definitions

  • the present invention relalates to high pressure, high temperature gate valves, particularly suitable for use in high pressure systems, such as those found in steam boilers oil refineries and oil field steam injection systems.
  • the present invention provides a gate valve in which the valve gate is adapted to seat on the valve seat in the closed position with good sealing pressure and in which the movement of fluid under pressure is prohibited until the downstream port starts to open which causes an increase in pressure on the gate forcing it against the smooth surface of the body of the valve and thus reduces cavitation.
  • a gate valve comprising a valve body having a bore extending therethrough defining an inlet and an outlet port for the flow or fluid under pressure, a valve gate movable vertically in a valve chamber across said bore between an open position in which said gate is above said bore in said chamber and a closed position in which said gate extends across said bore with its lower end in a part of said chamber recessed into the wall of the bore, said gate having a flat faced downstream wall which in the closed position seats on a flat faced seat surrounding said bore and having a wedge-shaped upstream wall which cooperates with a wedge-shaped wall in said chamber to force said downstream wall onto said flat seat whereby said fluid is only able to pass through said bore when the lower end of said gate is above the lower portion of the wall of said bore thus reducing caviation.
  • valve uses a flat gate seating on a flat and preferably interchangable seat, the gate having a wedge-shape on the upstream side which assists in forcing the seating surfaces together which is highly desirable in high pressure conditions.
  • the inlet and outlet ports are completely covered In the closed position which enables the valve to withstand extreme pressures.
  • the seat is removably attached in said chamber around the bore and suitably the seat is a separate part.
  • This exhangable seat facilitates repair and the seat can be made of any number of materials to best resist abrasion and/or corrosive fluids or gases.
  • the valve gate suitably has metal-to-metal seating surfaces and utilizes upstream pressure to assist seating and this pressure is not released until the gate starts to uncover the port and as such wash conditions are minimized.
  • a valve body which is suitably cast or forged is formed of at least two body members which are split on a plane normal to the axis of the bore, the body members being secured to each other to define the chamber and the bore, one of the members containing the seat and opening to the exterior of the valve body on an axis normal to the bore, the gate and the valve stem means extending through the chamber and the other body member providing a closure for the one body member.
  • the chamber of the valve which contains all the moving parts maybe thus completely machined ensuring consistent wall thickness.
  • the elimination of rough cast surfaces in the cavity reduces the tendency for fluids to cavitate and wash out the valve seats and distort the gate.
  • a machining process can produce a valve chamber to a very fine tolerance which ensures an accurate fit of the valve seat in the valve body and a closer fit between the valve gate and the valve seat. This fine tolerance in the manufacturing process permits interchangability of parts in the valves of the same port diameter.
  • valve of the present invention may be manufactured in practically any material that is presently available. Since all the parts are machined the operator of the plant can stock items which will fit many of the valves and eliminate the current need to transport valves from the field, sometimes by air, for repair. The accuracy of the machining process involved in the manufacture of all the parts allows the chamber to serve as a guide for the gate and limit wear and tear on the valve stem. A precise machine fit will result in reduced shear stress on the bolts and contributes to the valve's advantage in high pressure situations.
  • the valve of the present invention may be manufactured from a forging with internal chambers and parts completely machined and therefore can be made from any material that can be forged and indeed can be manufactured from bar stock and therefore any material which can be machined.
  • the other body member providing a closure for said one body member includes a spigot portion allowing a very close fit to resit radial and lineal stresses.
  • the present invention provides a protruberance which locates into the valve chamber also allows a very close fit to resist radial and lineal stresses.
  • valve stem means includes a valve stem extending through said chamber and said body having a threaded lower end cooperating with a threaded recess in said gate, said stem being axially rotatable in a bearing menas in said body to raise and lower said gate between said open and closed positions, said bearing means including a stuffing box, a lower seat an upper seat through which said stem extends, said stem inlcuding an integral collar located between said seats, said collar having tapered shoulders which forms a self-aligning seal with said upper and lower seats.
  • the upper seat is provided by the stuffing box which has a flange extending downwardly from the bottom thereof, defining with the valve body a cavity containing the collar with a sealing means trapped in a recess between said flange and said neck portion.
  • the packing or stuffing box of the valve of the present invention suitably utilizes pressure activated packing which is capable of containing high pressure and has an integral collar on the stem and complimentary seats in the body and stuffing box to form back pressure seats in either the open or closed positions such that pressure is only applied to the packing when the gate is travelling form the open to the closed positions or vice versa.
  • the stuffing box has back seat in both the open and closed position which limits pressure on the packing to periods when the gate is moving between the open and closed positions.
  • the limited pressure on the packing permits it to be changed while the valve is opened or closed without removing the pressure in the valve or removing the valve from the line.
  • the packing rings of the packing are suitably single complete pieces rather than being split, thus the stuffing box is completely isolated from the body cavity when in the extreme open or closed positions.
  • the present invention also provides a gate valve comprising a valve body defining an inlet and outlet port for the flow of fluid under pressure therethrough, a valve gate movable vertically in a chamber in said body across said bore between an open position in which said gate is above said bore, allowing communication between said ports and a closed position in which said gate extends across said bore and sealingly seats under pressure with a flat downstream face on a gate seat disposed around said bore on the downstream side of said gate, a valve stem extending through said body into said chamber having a threaded lower end cooperating with a threaded recess in said gate, said stem being axially rotatable in a bearing means in said body to move said gate between said open and closed position, said bearing means including a stuffing box, a lower seat and an upper seat in said body through which said stem extends, said stem including an integral collar located between said upper and lower seats, said collar having tapered shoulders which forms a self-aligning seal with said upper and lower seats, such that when said gate is in its fully
  • FIG. 1 is a sectional side-view taken along the line A--A in FIG. 2 of a gate valve according to a preferred embodiment of the present invention in the closed condition;
  • FIG. 2 is a sectional end view-taken along the line B--B in FIG. 1;
  • FIG. 3 is a sectional side view taken along line C--C in FIG. 4 of the gate valve of FIG. 1 in the open position;
  • FIG. 4 is a sectional end view taken along line D--D in FIG. 3;
  • FIG. 5 is an enlarged detail of the bearing of the stem bearing of the gate valve of FIGS. 1 to 5.
  • the gate valve comprises a valve body 1 having a horizontal passage 2 therethrough defining upstream and downstream ports and having threaded ends 3 for connecting to the conduits of a high temperature high pressure system.
  • the ports are opened and closed by a gate 4 having a flat smooth downstream surface 5 seating on a removable valve seat 6 disposed around the passage 2.
  • the seat 6 is a separate part that fits precisely into the machined ledge in the valve body 1, therefore, can be replaced or constructed of any suitable material depending upon the application.
  • the gate 4 in the closed position has its lower end extending into a recess 7 in the wall of the passage 2, which recess 7 forms part of the valve chamber 8 in which the gate moves between its open and closed positions.
  • the upstream face 21 of the valve gate 4 has a wedge-shape which cooperates with a similar surface 22 in the chamber 8 which provides sealing pressure for a tight seal between the downstream face 5 of the valve seat 6 and provides with the recess 7 of the chamber 8 that the ports are completely opened or totally covered when closed which enables it to stand extreme pressures.
  • the movement of the gate 4 between the open and closed position is effected by means of turning a hand wheel 9 mounted on a valve stem 10 having a threaded lower end 11 which turns in a threaded recess in the gate 4, the stem 10 also having a collar 12 disposed in a cavity between a seat 13 formed in a neck portion 101 said body 1 and a seat 14 on a stuffing box body 15 screwed into the neck portion 101 said body 1.
  • the stuffing box body 15 contains a Chevron-style packing 16 which is pressure energized and held in by a packing gland 17 screwed into said stuffing box body 15 forming a bearing for the valve stem 10.
  • the stuffing box body 15 has a downwardly extending flange 102 defining said cavity which is sealed by an O-ring 17 between it and said neck portion 101 of said valve body 1.
  • the collar 12 serves as a thrust bearing but also has tapered shoulders, suitably at about 30° which allow a self-aligning line seal and seat on two-way back seal seats 13 and 14 when the valve gate 4 is in its closed position when the back seal seat 14 is effective and open position when the back seal seat 13 is effective, thereby isolating the the stuffing box from the chamber except when the gate 4 is travelling between the open and closed positions.
  • the stuffing box is completely isolated in such position from the fluid pressure in the valve providing for the capability of changing the packing when required without removing the valve from the line in the open or closed condition and thus providing for simplicity of surface when required.
  • the valve body 1 has a main body portion 1b which is closed on one side thereof by a removable closure plate 1a having a flat surface mating with a corresponding flat surface on said main body portion, which are clamped together by bolts 20 and trapped sea 30, the main body portion 1b containing all the operational parts including the gate 4 and stem 10 and valve seat 6 and the cover plate 1a has a protuberance 1c which locates in the eccentric valve chamber 8 which allows a very close fit; resists both lineal and radial shear stresses and also traps the seal 30 in all directions.
  • the inner face of the protuberance 1c thus constitutes the wall 22 of the chamber 8.
  • the gate valve of the present invention has valve ports which are completely open or totally covered when closed, has body parts which may be made of a material best suited to resit corrosive fluids or gases and are not just coated, will allow for the containment of high pressure high high temperature fluids or gases, provides for the stuffing box to be completely isolated from the body chamber except when the gate is travelling through the opposite open or closed condition, provides for interchangable seats of material best suited for service conditioning of the valve, allows for the body and cover to be machined from forging and thus from superior material, allows for changing of the packing, allows for close machining tolerance of all parts to allow the gate chamber to also be a guide for the gate and provides for close tolerances which ensure complete interchange of all parts, i.e., all seats will fit any seat chamber. Further all body cavity and matching cover parts may be completely machined for fit to contain a gasket seal and to reduce shear stresses on bolting.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Sliding Valves (AREA)
  • Lift Valve (AREA)
  • Details Of Valves (AREA)
US07/436,120 1987-11-26 1989-11-13 Gate valve Expired - Lifetime US4944488A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA000552900A CA1301734C (en) 1987-11-26 1987-11-26 Gate valve
CA552900 1987-11-26

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US07231131 Division 1988-08-11

Publications (1)

Publication Number Publication Date
US4944488A true US4944488A (en) 1990-07-31

Family

ID=4136951

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/436,120 Expired - Lifetime US4944488A (en) 1987-11-26 1989-11-13 Gate valve

Country Status (3)

Country Link
US (1) US4944488A (de)
EP (1) EP0400229B1 (de)
CA (1) CA1301734C (de)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5289840A (en) * 1993-02-25 1994-03-01 Merrill Manufacturing Company, Inc. Yard hydrant
US5711509A (en) * 1996-07-01 1998-01-27 Eltec Inc. Isolation gate and frame assembly
US20020005502A1 (en) * 2000-06-01 2002-01-17 Roger Massey Bar-stock ball valve
US20060226390A1 (en) * 2005-04-12 2006-10-12 Hsu-Nan Liu Adjusting lever for a gas flow controller
US20070040141A1 (en) * 2005-08-16 2007-02-22 Fisher Controls International Llc Packing nut for control valve
US20100065769A1 (en) * 2008-09-15 2010-03-18 Weco Armaturen Gmbh Slide valve
US8439073B2 (en) 2010-09-10 2013-05-14 Hamilton Sundstrand Corporation Gate valve
US20140209827A1 (en) * 2013-01-30 2014-07-31 Wan-Rong Kung Valve

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE29611546U1 (de) * 1996-07-04 1996-09-19 WECO Armaturen GmbH, 51588 Nümbrecht Schieberorgan mit Monoblockgehäuse

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US127951A (en) * 1872-06-18 Improvement in stop-valves
US571880A (en) * 1896-11-24 lunken
US589725A (en) * 1897-09-07 And harvey m
US1020449A (en) * 1911-11-21 1912-03-19 Henry H Riggin Valve.
US1451473A (en) * 1919-12-20 1923-04-10 William E Pulverman Valve
US1625698A (en) * 1926-11-06 1927-04-19 William H Barton Packing for gate valves
US2678802A (en) * 1950-12-22 1954-05-18 Fairbanks Company Seat ring means for portways of gate valves or the like
US2787439A (en) * 1952-02-20 1957-04-02 Crane Co Valve construction
US3297299A (en) * 1964-06-30 1967-01-10 Acf Ind Inc Gate valve seat skirt
US3377049A (en) * 1965-10-24 1968-04-09 Joseph H. De Frees Gate valve
US3963214A (en) * 1974-11-26 1976-06-15 Mueller Co. Resilient seated gate valve with split body
US4223868A (en) * 1979-04-10 1980-09-23 Mueller Co. Resilient seated gate valve
US4434967A (en) * 1982-08-23 1984-03-06 Axelson, Inc. Valve self-relieving seats

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1260729A (fr) * 1960-03-31 1961-05-12 Loire Atel Forges Vanne perfectionnée
US3249117A (en) * 1962-06-07 1966-05-03 Grove Valve & Regulator Co Gate valve
FR2044042A5 (de) * 1969-05-07 1971-02-19 Pont A Mousson

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US127951A (en) * 1872-06-18 Improvement in stop-valves
US571880A (en) * 1896-11-24 lunken
US589725A (en) * 1897-09-07 And harvey m
US1020449A (en) * 1911-11-21 1912-03-19 Henry H Riggin Valve.
US1451473A (en) * 1919-12-20 1923-04-10 William E Pulverman Valve
US1625698A (en) * 1926-11-06 1927-04-19 William H Barton Packing for gate valves
US2678802A (en) * 1950-12-22 1954-05-18 Fairbanks Company Seat ring means for portways of gate valves or the like
US2787439A (en) * 1952-02-20 1957-04-02 Crane Co Valve construction
US3297299A (en) * 1964-06-30 1967-01-10 Acf Ind Inc Gate valve seat skirt
US3377049A (en) * 1965-10-24 1968-04-09 Joseph H. De Frees Gate valve
US3963214A (en) * 1974-11-26 1976-06-15 Mueller Co. Resilient seated gate valve with split body
US4223868A (en) * 1979-04-10 1980-09-23 Mueller Co. Resilient seated gate valve
US4434967A (en) * 1982-08-23 1984-03-06 Axelson, Inc. Valve self-relieving seats

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5289840A (en) * 1993-02-25 1994-03-01 Merrill Manufacturing Company, Inc. Yard hydrant
US5711509A (en) * 1996-07-01 1998-01-27 Eltec Inc. Isolation gate and frame assembly
US20020005502A1 (en) * 2000-06-01 2002-01-17 Roger Massey Bar-stock ball valve
US7025330B2 (en) * 2000-06-01 2006-04-11 Parker & Harper Companies, Inc. Bar-stock ball valve
US20060226390A1 (en) * 2005-04-12 2006-10-12 Hsu-Nan Liu Adjusting lever for a gas flow controller
US20070040141A1 (en) * 2005-08-16 2007-02-22 Fisher Controls International Llc Packing nut for control valve
US7980530B2 (en) * 2005-08-16 2011-07-19 Fisher Controls International Llc Packing nut for control valve
US20100065769A1 (en) * 2008-09-15 2010-03-18 Weco Armaturen Gmbh Slide valve
US8439073B2 (en) 2010-09-10 2013-05-14 Hamilton Sundstrand Corporation Gate valve
US20140209827A1 (en) * 2013-01-30 2014-07-31 Wan-Rong Kung Valve
US8870155B2 (en) * 2013-01-30 2014-10-28 Wan-Rong Kung Sleeve driven valve

Also Published As

Publication number Publication date
CA1301734C (en) 1992-05-26
EP0400229B1 (de) 1994-03-23
EP0400229A1 (de) 1990-12-05

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